Spot welding machine



FIG. 1 is a top plan, elevational, right hand quartering perspective view of a spot welding machine embodying the present design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a right hand end view thereof; and,

FIG. 7 is a left hand end view thereof. 

The ornamental design for a spot welding machine, as shown and described. 